It is known that phosphorus-containing groups can be chemically incorporated into hydrocarbon polymers. This incorporation of phosphorus causes changes in the properties of the resulting material. These changes are, for example, resistance to ignition and combustion, improved adhesion to polar solids such as glass, ceramics, metals, etc., improved dyeability, increased hydrophilic properties, and the formation of a resultant material that is potentially suitable as an ion exchange resin precursor.
Phosphorylated polystyrene materials are generally formed by polymerization of a phosphorus-containing monomer, as in U.S. Pat. No. 3,051,740-Abramo et al, or by a chemical post modification of an existing polymer backbone with reactive phosphorus intermediates, as in the Journal of Applied Polymer Science, Vol. 18, P. 1969-1986 (1974).
The resultant products of the first method are generally intractable gels or low molecular weight products and are not suitable for most commercial applications. The second method is undesirably restricted in that few chemical reactions suitable for post modification of polystyrene are known which yield resultant products that do not have an unacceptable molecular weight charge or wherein the method used requires only a one-step reaction in order to provide a desirable phosphorylated material.
These problems were solved by the method of this invention which provides a direct, one reaction step process without substantial polymer chain degradation of gellation. The resultant product of this invention is a unique phosphorylated polystyrene having fire-resistance properties suitable for forming television cabinets.